I think PF contributions to be made since the time the company becomes eligible to the act.
However seniors can guide better.
Another thing is there is no need to worry.
Each one of you will have a PF Account Number.
All the PF contributions, the interest earned there on are tax-free in your hand.
This act as a retirement solution and a fixed deposit to be utilized in the later part of our life.
You can always track the amount deposited in your PF Account.
I have shared link to the PF Act articles and have highlighted the important pointers below:
PF Act applies to any organization having more than 20 employees.
Once covered under PF Act, the company continues to be covered under the Act even if the employment drops below 20 thereafter at any time.
Employer not to reduce wages:
The clause states that in order to contribute for your PF, he can not lower the wages of yours. Now wages are payable to labours. Since you all are salaried employees, your gross should not go down. only 12% of your contribution is allowed as deduction so that your contribution is paid and deposited in your PF account. In order to pay the company's contribution, the company can however adjust from other components accordingly in such way that they do not reduce your gross, if your gratuity, bonus etc is covered in your ctc, such reduction do not violate the statutory compliance.
EPF Act 1952, EPF Act In India, EPF Rules And Regulations, EPF Rules For Withdrawal
http://epfindia.com <link fixed>